Can Common and Ground Wires be Connected Together in a Breaker Box?

Asked Jul 3, 2009, 09:53 AM
ó
9 Answers

I am using a spare bedroom for a workshop, and have installed extra lighting, a central vacuum and various power tools. The existing outlets are on two circuits, each with a 15 amp breaker. Both circuits are shared with other rooms and I occasionally overload the circuit and have to reset one or the other of the breakers.

I want to add two new dedicated circuits from the main breaker, each to a double gang outlet box containing two receptacles, giving me two four plug outlets. To each two gang box I ran three 10ga wires in flex pipe, (what we used to call greenfield), a red for power, white for neutral, and green for ground.

They each go to the only breaker box, which has a 2Ē pipe connected to the meter six inches away. There are places to add eight new circuit breakers, but it looks like the ground terminal (where all the bare copper wires are connected) is directly behind the neutral, (where the white return wires are) and most of the terminals on both of them already have wires connected. I canít turn off the main power to the box, itís wired directly to the meter with what looks like two # 6 stranded cables to the two main copper strips that supply power to the breakers, and a white to the common. I donít see a dedicated bare copper cable to the ground connector.

So, I have two #10 white common wires and two # 10 green ground wires all going to basically the same place, and the two red wires that will each connect to a new 30 amp breaker. The hot wires to the breakers will be easy, but there is not room for the two grounds on the strip with all the other bare copper wires, nor the two white neutrals on the strip with all the other white wires. The terminal with the ground wires is almost impossible to get to or even see with all the other wires in front of it.

My questions are:

Can I pull a wire off the common and pigtail it to the two neutrals, and add a new wire to connect back to the lug, and do the same thing with the ground wires?

Can I hook up two wires together under one lug? It does not look like there is room.

Do I have to hook the ground on the same terminal as the other bare copper wires, or just put any of these four wires anywhere I can get them, on either of the strips that have all the other common and ground wires? They all show to be connected when I test for continuity with an OHM meter.

Can I add new connector strips in the box? That would probably be a major undertaking, and there seems to be neither room in the box nor the strength of will in myself for that.

Thanks in advance for any input. I searched the forum before posting, but everything I read about the neutral and ground wires seemed to be contradicted by the next, and Iím looking for a simple answer to a simple problem. I may have over done it a little using 10 ga. Solid and 30 amp breakers, but Iím really tired of going out at all hours to reset the breakers.

There is a great deal to go through, I will have to come back with more detail.

However, a few comments:

You cannot use 30 amp breaker to protect a 15 or 20 amp receptacle. You may use #10 wire, but it will not fit in the device terminals.

Not all panels have Main Breakers IN THEM. There can be a Main Breaker elsewhere.

The panel must have a Main Breaker ahead of it someplace. It can be outside ahead of the meter, which is unusual.

If the Panel only has 6 branch circuit breakers, these 6 breakers can act as the Main.
This is called the "Six Switch Rule",and NO MORE breakers can be added without having one Main Breaker ahead of the panel.

Grounds and neutrals ONLY connect together in an enclosure that contains the Main Breaker.

All breaker boxes I have seen, have a main disconnect breaker. If u don'thave one, I would think the box is illegal.

Ground and neutral can be hooked to same grounding strip.

Chuck

There is a double throw 60 AMP at the top, with the other breakers, but I don't see how it could shut off power to the copper buss in the center that the other breakers contact to make them hot, or does it?
In the light of day I noticed that most of the mess around the ground / neutral connector terminals was caused by a giant dirt dobber nest. After breaking it up with a rubber mallet and blowing it out with compressed air I could see that the terminals were attached together, so I just piggybacked both my ground and neutral wires in with some of the others on the front buss. I put in the two 30 amp breakers and all seems to be working fine, except that the breaker on one of the circuits I was having a problem with won't stay in the ON position at ALL, even when pulled from the box. I must have worn it out from so much wear and tear!
As you can see in the photo, the breaker box is connected by conduit to the meter, so I don't see how power could be cut to the entire box without pulling the meter head. And I don't see how it could be illegal (up to now) because it's been here since the house was built in the late 70's. But then what do I know? I couldn't tell a dirt dobber nest from a tangled mass of ground wires until I saw it in the bright sunlight this morning. So I could be wrong. At any rate, anytime I get around anything electrical I assume it is surging with potentially deadly high volts/amps/watts/ and treat it as such, and that's what I did this time.
As to the 30 Amp breaker and #10 wire to the plugs rated at 20 amps, I figured you can never have too much copper, and since I'm feeding two plugs in a double gang box, that's just 15 amps each! Yeah, I know it doesn't work that way.
I used the screws instead of the push-in connectors which were too small anyway, and when I did the second one something from my long ago past when I worked in the 70's as helper to my Master Electrician Brother came back to me and I simply looped the wire around the screw on the first receptacle and went on to the 2nd one. Actually I'll never be using over 1500 - 2000 watts on either of the two four plug outlets. That would be... (lets see... if I remember correctly, watts divided by voltage = amps... )I should never pull over 12 to 17 amps through that 30 amp breaker with my #10 wire.
The main thing is that when my girlfriend turns on a blow dryer or when I come in hot & sweaty from the 110 degree Texas heat and plop down in front of my personal 110V AC unit I placed in the window beside my recliner... it won't blow a breaker, sending me back out into the hot sun to... well, you get it!

Thanks for the input, and if you see any flaws in my logic let me know.

With the feed coming directly from the meter to the Main Lugs, the service has no Main Breaker, it was illegal in 1970 and still is.

If a short occurs in the busbar of the panel, that which all the branch breakers plugs onto, this panel will blow off the wall. Good thing it is on a brick wall.

Since the Main Breaker should reside in this panel, the neutrals and grounds do get connected together here. Using one hole for multiple conductors is only allowed if the terminal is rated for more than one wire.Another ground bus bar can be added.

The other flaw is you insist on using a 30 amp breaker to protect a 15 or 20 amp duplex.

Under no circumstances will this be allowed, does not comply with any Code or standard practice.

I do not recommend to anyone reading this doing what you have done or planned.

With the feed coming directly from the meter to the Main Lugs, the service has no Main Breaker, it was illegal in 1970 and still is.

If a short occurs in the busbar of the panel, that which all the branch breakers plugs onto, this panel will blow off the wall. Good thing it is on a brick wall.

Since the Main Breaker should reside in this panel, the neutrals and grounds do get connected together here. Using one hole for multiple conductors is only allowed if the terminal is rated for more than one wire.Another ground bus bar can be added.

The other flaw is you insist on using a 30 amp breaker to protect a 15 or 20 amp duplex.

Under no circumstances will this be allowed, does not comply with any Code or standard practice.

I do not recommend to anyone reading this doing what you have done or planned.

OK, now I think I understand the problem:
If I were to plug in a string of 35 100w light bulbs, which would be about a 30 amp load. The 30 amp breaker would be OK and the # 10 wire would have no problem handling the load. But the receptacle, rated at only 20 amps could have a problem, overheat, and create a potentially hazardous situation that would not trip the 30 amp breaker.
So, if I simply change out the two 30 amp breakers to 20 amp, will that address the problem? Hopefully I don't have to change the wire too.
Ten gauge wire will not stop a 20 amp breaker from tripping on an overload, will it? Is there any difference between identical circuits with 20 amp breakers and 20 amp plugs if one had 14AWG, wire, the other 12AWG, and the third 10AWG? They would all trip just like they are designed to in the event of a problem, right?

As far the ground bus, I'm not going to worry about putting two wires under the same screw. Every third hole is a little bigger than the others, so I'll assume that rates it for more than one wire.

I just don't see how the breaker box could be illegal. Maybe the codes are different because I'm outside the City limits, in Harris County, but there still have to be standards. The subdivision was started in the mid 70's and my house was built in 1978. There are over 350 houses in this subdivision and I looked at four other houses in my area and every one had the meter attached directly to a GE box that looked just like mine, from the outside at least. When I bought the house in 1999, my Realtor had me hire a certified inspector who came out and went over the house from top to bottom. I think I paid him $250.00 and he was here all day. He gave me a list of everything that was wrong, and I made the seller fix most of them. He was bonded and I still have the certificate he provided, which I remember having to fax to the mortgage company.

When I was finishing up today, I flipped the 60 amp breaker off and it killed the AC compressor which I was standing next to. I wouldn't have thought anything about it, except that it also killed the air compressor and a big fan I had set up yesterday and that worked off an extension cord that was plugged in 50 or 60 feet away. I thought that strange, so I checked and all the power to the house was off, even though all the other breakers were still on. Upon closer inspection, I noticed it is wired different than the other breakers. The photo I sent yesterday shows the feed from the meter does go directly to the main bus, but look at the photo I sent today. The 60 amp I flipped today that cut off the power to everything looks like it's wired different... the cables coming from it do not go out of the box like the wires on every other breaker. I don't see how, since I can see the main feeder cables going directly to the copper bus in the center of the box, but that breaker does shut off power to the entire house. The box is a GE Model TX1412RH. I tried to find a schematic or specifications on the GE website with no luck. But look at the photo I sent and see what you think.

Great, I am glad you have seen the light, so to speak, with using a 20 amp breaker for 15 or 20 amp receptacles. (Yes, 15 amp receptacles can be on a 20 amp breaker, only with #12 wire.)

Since a breaker protects the wire, having a wire larger than a breaker is fine, such as #10 on a 20 amp breaker, or even 15. But using a small wire only rated 20 amps protected by a 30 amp breaker will allow more current than the wire is rated to flow, and be a potential fire hazard.

Your service is perplexing, based on your photos and observations.

The last photo you provided has more light inside, and now appears to be some sort of split bus for some reason.

Any chance of you hiring an electrician or your brother to look at this panel and figure out exactly what is going on?

Well, my brother is retired and lives in Dallas so the chances of getting him here are slim and none. If I hire an electrician I may be in for a big bill if there is a code violation.
There is one more clue that may shed some light on the situation. If the box were not protected and... lets say something happened to cause something hot to go directly to ground. Best case scenario the wire would a # 14 and act as a fuse and blow in two, worst case the same thing happens when a high wind blows a two ton chunk of flying metal crashing into the box and the box explodes.
But if the box had a main circuit breaker it would trip. When I said I turned the 60 amp off and it shut off power to the whole house... well, that was not exactly what happened. I had everything hooked up and working, but it was sort of a mess.. wires everywhere. So when I went to take another photo to post, I wanted it to look neat so Thought I'd dress back the wires a little. I was standing on a half sheet of plywood with a inch thick rubber doormat on top and had a heavy glove on one hand. I was using the fiberglass handle of a rubber mallet to push them back. The #10 was really hard to dress and one of them just wouldn't stay back. I had an old, dull pair of diagonal cutters in my back pocket. I had experienced how tough the insulation is on the #10 wire, and the cutters were so dull I didn't think they'd cut hot butter let alone the insulation in the wire. So I gripped it very lightly with the cutters and some how they cut through to copper on the #10 and the cutters touched a bare ground wire from a piece of romex and when that's when the 60 amp breaker tripped, probably just like it's supposed to.
Thanks for all your advice, and I will have an electrician friend of mine to take a look and let you know it turns out.

Add your answer here.

Check out some similar questions!

OK... Im wiring up a detached building and I have ran into a small problem. Might be a dumb question but here goes. Im feeding from the box under my meter out to the shed. Im running 6/3 w gnd. I got the shed sub panel under control. But in the box under my meter for the fround wire, there is not...

Is it proper to connect the ground and neutral to the neutral buss? I am installing a sub panel from a 200amp svc to a 125 service using 6g. My sub box does not have a separate ground buss rather only 2 neutral buses with a crossbar. I was informed that I can put the neutral and ground on that...

I'm changing out some 2 prong receptacles in an old home that has no ground wire (ie, the electrical cables have a hot and neutral, no ground wire). I'd like to install new 3 prong receptacles. Is this OK? What are the implications of doing this? Thanks!

Okays people can call and they hear the phone ring and ring, but my phone has no dial tone and won't ring, but if I were to pick up the phone and someone happens to be calling at the same time I can hear it ring. I have att, and could it be the outside box, and if so how would I connect it back,...

I recently had some indications of power surges in my home and called the electric company. The technician they sent out said that the ground had settled and did some work on the box in my front yard (our power lines are underground) and to the ground wires on the exterior of my home. After he...